Method for estimating physical condition, physical condition estimation apparatus, and non-transitory computer-readable recording medium

ABSTRACT

A method of controlling a device includes: obtaining information related to a body surface temperature of a person by detecting the body surface temperature of the person by a thermal camera, estimating a deep body temperature of the person on the basis of the information related to the body surface temperature of the person, detecting the person&#39;s condition on the basis of the deep body temperature of the person, and controlling an operation of the device according to the detected person&#39;s condition.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation application of U.S. patent application Ser. No.15/350,161, filed Nov. 14, 2016, which claims the benefit of U.S.Provisional Pat. Appl. No. 62/261,457, filed Dec. 1, 2015, and priorityto Japanese Pat. Appl. No. 2016-101969, filed May 20, 2016. Thedisclosure of each of the above-identified applications is hereinincorporated by reference in its entirety.

BACKGROUND 1. Technical Field

The present disclosure relates to a method for estimating a physicalcondition, a physical condition estimation apparatus, and anon-transitory computer-readable recording medium storing a program.

2. Description of the Related Art

In Japanese Unexamined Patent Application Publication No. 2002-272708, atechnique for determining a person's physical condition, such as stress,fatigue, sleepiness, or an arousal level, on the basis of a pulse wavesignal obtained by measuring a pulse wave caused by blood circulation isdisclosed.

SUMMARY

In one general aspect, the techniques disclosed here feature a methodfor estimating a physical condition used by a computer. The methodincludes simultaneously measuring blood flow volumes of at least twobody parts of a person and estimating a person's physical condition onthe basis of the blood flow volumes of the at least two body partsmeasured in the simultaneously measuring.

With the method for estimating a physical condition in the presentdisclosure, a person's physical condition can be estimated withoutpreliminary calibration.

It should be noted that general or specific embodiments may beimplemented as a system, a method, an integrated circuit, a computerprogram, a computer-readable recording medium such as a compact discread-only memory (CD-ROM), or any selective combination thereof.

Additional benefits and advantages of the disclosed embodiments willbecome apparent from the specification and drawings. The benefits and/oradvantages may be individually obtained by the various embodiments andfeatures of the specification and drawings, which need not all beprovided in order to obtain one or more of such benefits and/oradvantages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating the configuration of a physicalcondition estimation apparatus according to a first embodiment;

FIG. 2 is a block diagram illustrating an example of a detailedconfiguration of a blood flow measuring unit illustrated in FIG. 1 ;

FIG. 3 is a block diagram illustrating an example of a detailedconfiguration of a physical condition estimation unit illustrated inFIG. 1 ;

FIG. 4 is a diagram illustrating an example of Russell's circumplexmodel;

FIG. 5 is a diagram illustrating an example of output control performedby the physical condition estimation apparatus illustrated in FIG. 1 ;

FIG. 6 is a flowchart illustrating an overview of the operation of thephysical condition estimation apparatus illustrated in FIG. 1 ;

FIG. 7 is a diagram illustrating an example of output control performedby the physical condition estimation apparatus in a first example;

FIG. 8 is a flowchart illustrating an example of an output controlmethod used by the physical condition estimation apparatus in the firstexample;

FIG. 9 is a diagram illustrating an example of output control performedby the physical condition estimation apparatus in a second example;

FIG. 10 is a flowchart illustrating an example of an output controlmethod used by the physical condition estimation apparatus in the secondexample;

FIG. 11 is a flowchart illustrating an example of an output controlmethod used by the physical condition estimation apparatus in a thirdexample;

FIG. 12 is a block diagram illustrating the configuration of a physicalcondition estimation apparatus according to a second embodiment;

FIG. 13 is a block diagram illustrating an example of a detailedconfiguration of an emotion estimation unit illustrated in FIG. 12 ;

FIG. 14A is a diagram illustrating an example of a mode in which theemotion estimation unit illustrated in FIG. 12 uses Russell's circumplexmodel;

FIG. 14B is a diagram illustrating an example of Schlosberg's conicmodel used by the emotion estimation unit illustrated in FIG. 12 ;

FIG. 15 is a block diagram illustrating an example of a detailedconfiguration of the physical condition estimation unit illustrated inFIG. 12 ;

FIG. 16 is a flowchart illustrating an overview of the operation of thephysical condition estimation apparatus illustrated in FIG. 12 ;

FIG. 17 is a diagram illustrating an example of output control performedby a physical condition estimation apparatus in an example of the secondembodiment;

FIG. 18 is a diagram illustrating an example of output control performedby a physical condition estimation apparatus according to a firstmodification of the second embodiment;

FIG. 19 is a diagram illustrating an example of output control performedby a physical condition estimation apparatus according to a secondmodification of the second embodiment;

FIG. 20 is a flowchart illustrating an example of estimation of anepileptic seizure and an output control method;

FIG. 21 is a diagram illustrating an example of output control dependingon a result of detection of deep body temperature; and

FIG. 22 is a flowchart illustrating an example of an output controlmethod depending on the result of the detection of the deep bodytemperature.

DETAILED DESCRIPTION Underlying Knowledge Forming Basis of the PresentDisclosure

Pulse pressure varies between individuals. In the technique disclosedJapanese Unexamined Patent Application Publication No. 2002-2727708,therefore, calibration (adjustment) in which the pulse pressure of asubject is set needs to be performed beforehand, that is, before thesubject's physical condition is determined.

One non-limiting and exemplary embodiment provides a method forestimating a physical condition without preliminary calibration and thelike.

A method for estimating a physical condition according to an aspect ofthe present disclosure is a method for estimating a physical conditionused by a computer. The method includes simultaneously measuring bloodflow volumes of at least two body parts of a person and estimating aperson's physical condition on the basis of the blood firm volumes ofthe at least two body parts measured it be simultaneously measuring.

According to the above aspect, the person's physical condition can beestimated without preliminary calibration even if the computer estimatesthe person's physical condition by measuring blood flow volumes thatvary between individuals.

In addition, for example, in the simultaneously measuring, blood flowvolumes of a first body part, whose blood flow volume hardly variesdepending on the person's physical condition, and a second body part,whose blood flow volume varies depending on the person's physicalcondition, may be measured as the blood flow volumes of the at least twobody parts.

Here, for example, the first body part may be the person's forehead. Thesecond body part may be at least one of the person's nose, the person'slips, one of the person's hands or feet, the person's neck, and portionsunder the person's eyes.

In addition, for example, in the simultaneously measuring, a blood flowvolume of the person's forehead and a blood flow volume of portionsunder the person's eyes may be measured as the blood flow volumes of theat least two body parts, in the estimating the person's physicalcondition, hours of sleep of the person may be estimated as the person'sphysical condition.

In addition, for example, in the simultaneously measuring, a blood flowvolume of the person's forehead and a blood flow volume of at least oneof the person's nose, the person's lips, and one of the person's handsor feet may be measured as the blood flow volumes of the at least twobody parts. In the estimating the person's physical condition, a senseof warmth and coldness of the person may be estimated as the person'sphysical condition.

In addition, for example, in the simultaneously measuring, a blood flowvolume of the person's forehead and a blood flow volume of the person'sneck may be measured as the blood flow volumes of the at least two bodyparts. In the estimating the person's physical condition, whether theperson's shoulders are stiff may be estimated as the person's physicalcondition.

Furthermore, for example, the method may further include estimating theperson's emotion on the basis of a physiological value of the person andcorrecting the person's physical condition estimated in the estimatingthe person's physical condition on the basis of the person's emotionestimated in the estimating the person's emotion.

Here, for example, the physiological value of the person may be one ofthe blood flow volumes of the at least two body parts.

In addition, for example, the physiological value of the person may be ablood flow volume of a body part different from the at least two bodyparts.

In addition, for example, the physiological value of the person may beat east one of complexion, a heartrate, venation in the heartrate, aratio of a low frequency component to a high frequency component of thevenation in the heartrate, R-R intervals, a pulse wave, variation in thepulse wave, a brain wave, a respiratory rate, respiratory volume, bloodflow, variation in the blood flow, blood pressure, variation in theblood pressure, oxygen saturation, movement of a body part, movement ofa body muscle, movement of a facial muscle, body temperature, skintemperature, skin conductance, skin resistance, the amount of sweat, anda sweating rate.

In addition, for example, in the simultaneously measuring, the bloodflow volumes of the at least two body parts may be measured in anoncontact manner by radiating light having a certain wavelength ontothe at least two body parts and receiving light having wavelengthsdifferent from each other.

Here, for example, in the simultaneously measuring, the blood flowvolumes of the at least two body parts may be measured using a camera.For example, at least one of the simultaneously measuring and theestimating may be performed by a processor.

In addition, a physical condition estimation apparatus includes a bloodflow measurer that simultaneously measures blood flow volumes of atleast two body parts of a person and a physical condition estimator thatestimates the person's physical condition on the basis of the blood flowvolumes of the at least two body parts measured by the blood flowmeasurer. For example, at least one of the blood flow measurer and thephysical condition estimator may include a processor.

It should be noted that these genera or specific aspects may beimplemented as a system, a method, an integrated circuit, a computerprogram, a computer-readable recording medium such as a CD-ROM, or anyselective combination thereof.

The method for estimating a physical condition according to the aspectof the present disclosure and the like will be specifically describedhereinafter with reference to the drawings. Embodiments that will bedescribed hereinafter are specific examples of the present disclosure.Values, shapes, materials, components, arrangement positions of thecomponents, and the like described in the following embodiments areexamples, and do not limit the present disclosure. Among the componentsdescribed in the following embodiments, ones not described in theindependent claims, which define broadest concepts, will be described asarbitrary components.

First Embodiment Configuration of Physical Condition EstimationApparatus

FIG. 1 is a block diagram illustrating the configuration of a physicalcondition estimation apparatus 10 according to a first embodiment.

As illustrated in FIG. 1 , the physical condition estimation apparatus10 includes a blood flow measuring unit 11, a physical conditionestimation unit 12, and a output control unit 13. The physical conditionestimation apparatus 10 is implemented as a computer or the like.

Blood Flow Measuring Unit 11

FIG. 2 is a block diagram illustrating an example of a detailedconfiguration of the blood flow measuring unit 11 illustrated in FIG. 1.

As illustrated in FIG. 2 , the blood flow measuring unit 11 includes acamera section 111 and a blood flow volume measurement processingsection 112 and simultaneously measures blood flow volumes of at leasttwo body parts of a person. The at least two body parts are a first bodypart, whose blood flow volume hardly varies depending on the person'sphysical condition, and a second body part, whose blood flow volumevaries depending on the person's physical condition. For example, thefirst body part is the person's forehead, and the second body part isthe portions under the person's eyes, the person's nose or person'slips, one of the person's hands or feet, or the person's neck.

More specifically, the camera section 111 is a laser speckle camera, alaser Doppler blood-flowmeter, or the like. The camera section 111radiates light having a certain wavelength onto the at least two bodyparts and receives light having wavelengths different from each other.The blood flow volume measurement processing section 112 measures theblood flow volumes of the at least two body parts in a noncontact manneron the basis of the light received by the camera section 111 havingwavelengths different from each other.

The camera section 111 may be a camera or may be a device different froma camera, such as a milliwave sensor or a pulse oximeter, insofar as thecamera section 111 is capable of simultaneously measuring the blood flowvolumes of the at least two body parts.

Physical Condition Estimation Unit 12

FIG. 3 is a block diagram illustrating an example of a detailedconfiguration of the physical condition estimation unit 12 illustratedin FIG. 1 . FIG. 4 is a diagram illustrating an example of Russell'scircumplex model.

As illustrated in FIG. 3 , the physical condition estimation unit 12includes a blood flow volume obtaining section 121 and a physicalcondition estimation processing section 122 and estimates a person'sphysical condition on the basis of the blood flow volumes of the atleast two body parts measured by the blood flow measuring unit 11.

More specifically, the blood flow volume obtaining section 121 obtainsthe blood flow volumes of the at least two body parts measured by theblood flow measuring unit 11. The physical condition estimationprocessing section 122 estimates the person's physical condition on thebasis of the blood flow volumes of the at least two body parts obtainedby the blood flow volume obtaining section 121.

Here, it is preferable to measure blood flow volumes of the first bodywhose blood flow volume hardly varies depending on the person's physicalcondition, and the second body part, whose blood flow volume variesdepending on the person's physical condition, as the blood flow volumesof the at least two body parts. As described above, for example, thefirst body part is the person's forehead, and the second body part isthe person's nose, the person's lips, one of the person's hands or feet,or the person's neck, or the portions under the person's eyes. As aresult, the physical condition estimation unit 12 can estimate theperson's physical condition, without preliminary calibration, on thebasis of the blood flow volume of the second body part relative to theblood flow volume of the first body part.

In the present embodiment, a person's physical condition refers to theperson's condition other than emotions defined by Russell's circumplexmodel, which is a two-dimensional model illustrated in FIG. 4 . Theperson's physical condition, therefore, may be, for example, hours ofsleep, a sense of warmth and coldness, stiffness in the shoulders, aspot on the face, dryness of the skin, or the like.

If the blood flow measuring unit 11 measures blood flow volumes of theperson's forehead and the portions under the person's eyes as the bloodflow volumes of the at least two body parts, for example, the physicalcondition estimation unit 12 may estimate the hours of sleep of theperson as the person's physical condition. Since a person develops darkrings under the eyes and the blood flow volume of the portions under theperson's eyes decreases when the hours of sleep are short, the hours ofsleep of the person of the day can be estimated from the blood flowvolume of the portions under the person's eyes.

If the blood flow measuring unit 11 measures a blood flow volume of theperson's forehead and a blood flow volume of at least one of theperson's nose, the person's lips, and one of the person's hands or feetas the blood flow volumes of the at least two body parts, for example,the physical condition estimation unit 12 may estimate the sense ofwarmth and coldness of the person as the person's physical condition.Since the temperature of the person's nose becomes high relative to thetemperature of the person's forehead in a hot environment and thetemperature of a person's nose becomes low relative to the temperatureof the person's forehead in a cold environment, the sensor of warmth andcoldness of the person can be estimated from the blood flow volumes.

If the blood flow measuring unit 11 measures blood flow volumes of theperson's forehead and neck as the blood flow volumes of the at least twobody parts, for example, the physical condition estimation unit 12 mayestimate, as the person's physical condition, whether the person'sshoulders are stiff. Since a person's shoulders are (can become) stiffwhen the blood flow volume of the person's neck is low relative to theblood flow volume of the person's forehead, whether the person'sshoulders are stiff can be estimated from the blood flow volumes. Here,a headache may be estimated as the person's physical condition insteadof stiffness in the shoulders. Since a headache is likely to occur whenthe blood flow volume of a person's neck s low relative to the bloodflow volume of the person's forehead, whether the person has a headachecan be estimated from the blood flow volumes.

Although the first body part is the forehead here, the first body partmay be another body part. The first body part may be any body part whoseblood flow volume hardly varies depending on a person's physicalcondition, such as the mouth or an eyeball.

The blood flow measuring unit 11 may measure a blood flow volume of aperson's face every day. In this case, the physical condition estimationunit 12 can estimate, as the person's physical condition on the basis ofday-to-day variation in the blood flow volume, that a spot is likely tobe formed on a part of the person's face in which the blood flow volumehas decreased.

Output Control Unit 13

The output control unit 13 performs output control according to aperson's physical condition estimated by the physical conditionestimation unit 12.

FIG. 5 is a diagram illustrating an example of the output controlperformed by the physical condition estimation apparatus 10 illustratedin FIG. 1 . FIG. 5 illustrates a case in which hours of sleep of the dayof a person 50 estimated from the blood flow volumes of the forehead andthe portions under the eyes of the person 50 are output to a screen of amobile terminal 60 owned by the person 50, such as a smartphone.

The output control performed by the physical condition estimationapparatus 10 (output control unit 13) is not limited to the exampleillustrated in FIG. 5 , and includes output control such as displaycontrol, notification control, and device control described hereinafter.

Hours of Sleep

The output control unit 13 may predict when a person will become sleepy,for example, on the basis of the person's hours of sleep estimated bythe physical condition estimation unit 12 as the person's physicalcondition. If the physical condition estimation apparatus 10 isinstalled in a vehicle, the output control unit 13 may, when the timehas come, display a message urging the person to take a break on ascreen of a car navigation system or a mobile terminal of the person. Ifthe physical condition estimation apparatus 10 is installed in a spacewhere the person stays, the output control unit 13 may, when the timehas come, arouse the person by turning up lighting.

If the output control unit 13 determines that the person's accumulatedhours of sleep estimated by the physical condition estimation unit 12are short, the output control unit 13 may notify a company for which theperson is working that the person needs rest.

The output control unit 13 may notify, using a mobile terminal such as asmartphone, the person of the person's hours of seep estimated by thephysical condition estimation unit 12 as the person's concentration orproductivity of the day.

The output control unit 13 may determine, as the hours of sleep,information that takes into consideration hours of sleep of a pluralityof days including the day estimated by the physical condition estimationunit 12, not just the hours of sleep of the day.

The output control unit 13 may set an insurance fee for the person onthe basis of the person's hours of sleep of a plurality of daysestimated by the physical condition estimation unit 12 and notify theperson of the insurance fee. The insurance fee herein refers to a feefor life insurance, automobile insurance, or the like. Because a personis more likely to fall asleep at the wheel or contract alifestyle-related disease when the person's hours of sleep are shorterthan a certain value, an insurance fee of a person whose hours of sleepare relatively short may be set high and the person may be notified ofthe insurance fee.

Sense of Warmth and Coldness, Stiffness in Shoulders, Etc.

The output control unit 13 may control the air volume, the airtemperature, or a wind direction of an air conditioner installed in aspace where the person stays in accordance with a sense of warmth andcoldness estimated by the physical condition estimation unit 12 as theperson's physical condition.

If the physical condition estimation apparatus 10 is installed in avehicle and the physical condition estimation unit 12 estimates, as aperson's physical condition, that the person's shoulders are stiff, theoutput control unit 13 may control a seat heater included in the vehiclein such a way as to heat the person's shoulders in order to prevent orreduce the stiffness in the person's shoulders.

The output control unit 13 may notify, through a mobile terminal such asa smartphone, a person of the stiffness in the person's shouldersestimated by the physical condition estimation unit 12 as the person'sconcentration or productivity of the day. Furthermore, if the stiffnessestimated by the physical condition estimation unit 12 is high or if theperson's shoulders are often stiff, the output control unit 13 maysuggest, through the mobile terminal such as a smartphone, that theperson get a massage or go to a clinic, or may propose a method forreducing the stiffness. The output control unit 13 may propose anothermeans for reducing the stiffness in the person's shoulders.

If the physical condition estimation unit 12 estimates, as a person'sphysical condition, that a spot is likely to appear on the person'sface, the output control unit 13 may suggest, through a mobile terminalsuch as a smartphone, that the person get a massage, or may propose amethod for reducing the likelihood of a spot. The output control unit 13may propose another means for reducing the likelihood of a spot.

Operation of Physical Condition Estimation Apparatus 10

Next, the operation of the physical condition estimation apparatus 10will be described with reference to FIG. 6 . FIG. 6 is a flowchartillustrating an overview of the operation of the physical conditionestimation apparatus 10 illustrated in FIG. 1 . The operation of thephysical condition estimation apparatus 10 is achieved by the computerincluded in the physical condition estimation apparatus 10.

First, the physical condition estimation apparatus 10 simultaneouslymeasures the blood flow volumes of at least two body parts of a person(S11) Next the physical condition estimation apparatus 10 estimates theperson's physical condition on the basis of the blood flow volumes ofthe at least two body parts (S12). The physical condition estimationapparatus 10 then performs output control according to the estimatedphysical condition (S13).

Advantageous Effects, Etc.

As described above, with the method for estimating a physical conditionaccording to the present embodiment and the like, a person's physicalcondition can be estimated without preliminary calibration even when acomputer estimates the person's physical condition by measuring a bloodflow volume that varies between individuals.

More specifically, in the method for estimating a physical condition andthe physical condition estimation apparatus according to the presentembodiment, the blood flow volumes of at least two body parts of aperson, namely, for example, a body part whose blood flow volume hardlyvaries depending on the person's physical condition and a body partwhose blood flow volume varies depending on the person's physicalcondition, are simultaneously measured. As a result, the person'sphysical condition can be estimated, without preliminary calibration, onthe basis of the measured blood flow volumes of the at least two bodyparts.

Although a person's physical condition can be the hours of sleep, thesense of warmth and coldness, stiffness in the shoulders, a spot on theface, or dryness of the skin in the present embodiment, a person'sphysical condition is not limited to these. A person's physicalcondition may be a level of urgency at which the person wants to go to atoilet, a level of carsickness, a risk of heat shock, a risk of avascular disorder caused by an increase in blood pressure duringdefecation, a level of intoxication, driving skills, a hunger level, afatigue level, a depression level, or the like, instead. These exampleswill be described hereinafter as first to ninth examples.

First Example

In the first example, a case will be described in which the level ofurgency at which a person wants to go to a toilet is estimated as theperson's physical condition.

FIG. 7 is a diagram illustrating output control performed by thephysical condition estimation apparatus 10 in the first example. FIG. 8is a flowchart illustrating an example of an output control method usedby the physical condition estimation apparatus 10 in the first example.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the level of urgency at which the person wants to goto a toilet as the person's physical condition on the basis of themeasured blood flow volumes of the person's forehead and the portionsunder the person's eyes. When a person wants to go to a toilet andbecomes tense, the blood flow volume of the portions under the person'seyes becomes low relative to the blood flow volume of the person'sforehead. The level of urgency at which the person wants to go to atoilet, therefore, can be estimated.

If the physical condition estimation apparatus 10 in the present exampleis installed in a vehicle and estimates that the level of urgency atwhich the person wants to go to a toilet is equal to or higher than athreshold, the physical condition estimation apparatus 10 in the presentexample may display a public toilet 71 on a screen 70 of a carnavigation system as illustrated in FIG. 7 to guide the person to thepublic toilet 71.

As illustrated in FIG. 8 , the physical condition estimation apparatus10 may estimate the level of urgency at which the person wants to go toa toilet (S121). If the estimated level of urgency at which the personwants to go to a toilet is lower than the threshold (NO in S131), thephysical condition estimation apparatus 10 may guide the person to aclean toilet located within a certain distance (S132). On the otherhand, if the level of urgency at which the person wants to go to atoilet is equal to or higher than the threshold (YES in S131), thephysical condition estimation apparatus 10 may guide the person to aclosest available toilet regardless of cleanness (S133).

As described above, the physical condition estimation apparatus 10 mayuse a different guiding method depending on the estimated level ofurgency at which the person wants to go to a toilet.

The method for estimating the level of urgency at which a person wantsto go to a toilet as the person's physical condition is not limited tothe one based on the blood flow volumes of at least two body parts. Thelevel of urgency at which a person wants to go to a toilet may beestimated on the basis of variation in the person's heartrate or bloodpressure or the person's facial expression, instead. Since a person'sheartrate and blood pressure increase and the person's facial expressionchanges (e.g., clenches the teeth) when the person wants to go to atoilet, the level of urgency at which the person wants to go to a toiletcan be estimated. One, some, or all of the heartrate, the bloodpressure, and the facial expression may be used to estimate the level ofurgency at which a person wants to go to a toilet.

Second Example

In the second example, a case will be described in which the level ofcarsickness of a person is estimated as the person's physical condition.

FIG. 9 is a diagram illustrating an example of output control performedby the physical condition estimation apparatus 10 in the second example.FIG. 10 is a flowchart illustrating an example of an output controlmethod used by the physical condition estimation apparatus 10 in thesecond example.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the level of carsickness of the person as the person'sphysical condition on the basis of the measured blood flow volumes ofthe person's forehead and the portions under the person's eyes. Since aperson gets a carsick and becomes tense, the blood flow volume of theportions under the person's eyes becomes low relative to the blood flowvolume of the person's forehead. The physical condition estimationapparatus 10, therefore, can estimate the level of carsickness of theperson.

If the physical condition estimation apparatus 10 is installed in avehicle and estimates that the level of carsickness of a person is equalto or higher than a threshold, the physical condition estimationapparatus 10 may display a parking area 72 for taking a break on ascreen 70 of a car navigation system to guide a driver to the parkingarea 72 as illustrated in FIG. 9 . The method for notifying the driverof the person's physical condition, needless to say, is not limited tothis. For example, the physical condition estimation apparatus 10 maydisplay the person's physical condition on the screen 70 of the carnavigation system or an instrument panel or output a speech soundthrough a mobile terminal of the driver or a vehicle speaker, in orderto notify the driver of the person's physical condition. Any othermethod may be used.

As illustrated in FIG. 10 , for example, the physical conditionestimation apparatus 10 may estimate the level of carsickness of theperson (S121A). If the estimated level of carsickness of the person islower than a threshold (NO in S131A), the process may return to S11 andthe physical condition estimation apparatus 10 may estimate the level ofcarsickness of the person a certain period of time later. On the otherhand, if the estimated level of carsickness of the person is equal to orhigher than the threshold (YES in S131A), a device control signal forcontrolling a vehicle device such as brakes, an accelerator, or anactive suspension may be output (S133A).

As a result, the sensitivity of the accelerator or the brakes can bereduced in order to suppress a sudden start or stop and reduce the levelof carsickness of the person, or the active suspension can be madesofter in order to reduce vibration applied to the person's body. Bycontrolling a device in this manner, the person can be prevented fromthrowing up in the vehicle or an increase in the level of carsicknesscan be suppressed, even if the person is a child or hesitates to tellthe driver that he/she is carsick. If the vehicle is a taxi, the drivercan allow the person to get out before the person throws up, or declineto pick up the person.

The method for estimating the level of carsickness of a person as theperson's physical condition is not limited to the one based on the bloodflow volumes of at least two body parts. The level of carsickness may beestimated on the basis of a person's facial expression, heartrate, orblood pressure. Since a person's face becomes pale or looks unwell or atemporal correlation (ρmax) between the person's heartrate and bloodpressure decreases when the person is carsick, the level of carsicknessof the person can be estimated. The level of carsickness of the personmay be estimated using ρmax and/or the facial expression.

Third Example

In the third example, a case will be described in which the risk of heatshock of a person is estimated as the person's physical condition. Heatshock herein refers to a vascular disorder such as a faint, a myocardialinfarction, or a cerebral infarction caused by a sudden change in bloodpressure. Heat shock often occurs when a person undresses in a coldchanging room before bathing and the blood pressure suddenly increasesor when a person takes a hot bath and the blood pressure suddenlyincreases.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the risk of heat shock of the person as the person'sphysical condition on the basis of the measured blood flow volumes ofthe person's forehead and the portions under the person's eyes. Sincethe blood flow volume of the portions under a person's eyes is lowrelative to the blood flow volume of the person's forehead in a coldenvironment and the blood flow volume of the portions under the person'seyes is high relative to the blood flow volume of the person's foreheadin a hot environment, the risk of heat shock of the person can beestimated.

FIG. 11 is a flowchart illustrating an example of an output controlmethod used by the physical condition estimation apparatus 10 in thethird example.

As illustrated in FIG. 11 , for example, the physical conditionestimation apparatus 10 may estimate the risk of heat shock of a person(S121C). If the estimated risk of heat shock of the person is lower thana threshold (NO in S131C), the process may return to S11 and thephysical condition estimation apparatus 10 may estimate the risk of heatshock of the person a certain period of time later. On the other hand,if the estimated risk of heat shock of the person is equal to or higherthan the threshold (YES in S131C), a device control signal including aninstruction to turn on a heater may be output in order to increasetemperature around the person (S133C).

As a result, a sudden change in the person's blood pressure can besuppressed, and heat shock can be prevented.

The output control method used by the physical condition estimationapparatus 10 when the estimated risk of heat shock of the person isequal to or higher than the threshold is not limited to this. If theperson is in a changing room or a toilet, for example, the person may benotified of the risk and urged to use a heater. If the estimated risk ofheat shock of the person is equal to or higher than the threshold whenthe person takes a bath, for example, the physical condition estimationapparatus 10 may output a device control signal including an instructionto add water to the bath. As a result, the temperature of the bath canbe decreased, thereby suppressing a sudden change in the person's bloodpressure.

The method for estimating the risk of heat shock of a person as theperson's physical condition is not limited to the one based on the bloodflow volumes of at least two body parts. The risk of heat shock of aperson may be estimated on the basis of the person's blood pressure,instead. If the person's blood pressure can be constantly measured andhas become equal to or higher than a certain value, for example, thephysical condition estimation apparatus 10 can estimate that the risk ofheat shock is high.

Here, a plurality of thresholds may be provided instead of the certainvalue, and the risk of heat shock may be estimated stepwise. Thethreshold(s) of blood pressure used to determine the risk of heat shockmay be adjusted on the basis of a degree of arteriosclerosis. The degreeof arteriosclerosis can be estimated from pulse pressure (highest bloodpressure and lowest blood pressure) or a pulse wave propagation time.Any other method may be used.

The threshold(s) of blood pressure may be adjusted on the basis of ageor a water content level inside the body, instead of the degree ofarteriosclerosis. This is because when the water content level insidethe body is small, the blood pressure sharply changes, which can lead toheat shock. Another method may be used to adjust the threshold(s) ofblood pressure, insofar as the risk of heat shock can be estimated.

The degree of arteriosclerosis may be manually input on the basis of aresult of a medical examination, instead of being detected in anoncontact manner. The age, too, may be manually input.

If the blood pressure can be constantly measured, a warning or anotification may be issued in accordance with the degree ofarteriosclerosis or the water content level. Changes in the person'sblood pressure may be displayed to the person.

Fourth Example

In the fourth example, a case will be described in which a person's riskof a vascular disorder caused by an increase in blood pressure duringdefecation is estimated as the person's physical condition. Duringdefecation, a person pushes down hard, and the person's blood pressureincreases. This might cause a vascular disorder such as a faint, amyocardial infarction, or a cerebral infarction.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the risk of a vascular disorder caused by an increasein the blood pressure during defecation as the person's physicalcondition on the basis of the measured blood flow volumes of theperson's forehead and the portions under the person's eyes. Since theblood flow volume of the portions under a person's eyes becomes highrelative to the blood flow volume of the person's forehead duringdefecation, the risk of a vascular disorder caused by an increase in theblood pressure during defecation can be estimated.

If estimating that the risk of a vascular disorder caused by an increasein the blood pressure during defecation is equal to or higher than acertain value, the physical condition estimation apparatus 10 in thepresent example may notify the person of the result of the estimation tourge the person not to push down very hard or may control a showertoilet in such a way as to spray water around the person's anus to allowthe person not to push down very hard.

As a result, a sudden change in the person's blood pressure can besuppressed, and a vascular disorder can be prevented.

The method for estimating the risk of a vascular disorder caused by anincrease in the blood pressure during defecation as a person's physicalcondition is not limited to the one based on the blood flow volumes ofat least two body parts. The risk of a vascular disorder caused by anincrease in the blood pressure during defecation may be estimated from aperson's blood pressure, instead. If the person's blood pressure can beconstantly measured and has become equal to higher than a certain value,for example, the physical condition estimation apparatus 10 can estimatethat the risk of a vascular disorder caused by an increase in the bloodpressure during defecation is high.

Here, a plurality of thresholds may be provided instead of the certainvalue, and the risk of a vascular disorder caused by an increase in theblood pressure during defecation may be estimated stepwise. Thethreshold(s) of blood pressure used to determine the risk of caused byan increase in the blood pressure during defecation may be adjusted onthe basis of the degree of arteriosclerosis. The degree ofarteriosclerosis can be estimated from pulse pressure (highest bloodpressure and lowest blood pressure) or a pulse wave propagation time.Any other method may be used.

The threshold(s) of blood pressure may be adjusted on the basis of theage or the water content level inside the body, instead of the degree ofarteriosclerosis. This is because when the water content level insidethe body is low, the blood pressure sharply changes, which can lead to avascular disorder. Another method may be used to adjust the threshold(s)of blood pressure, insofar as the risk of a vascular disorder caused byan increase in the blood pressure during defecation can be estimated.

The degree of arteriosclerosis may be manually input on the basis of aresult of a medical examination, instead of being detected in anoncontact manner. The age, too, may be manually input.

If the blood pressure can be constantly measured, a warning or anotification may be issued in accordance with the degree ofarteriosclerosis or the water content level. Changes in the person'sblood pressure may be displayed to the person.

Fifth Example

In the fifth example, a case will be described in which the level ofintoxication of a person is estimated as the person's physicalcondition.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the level of intoxication of the person as theperson's physical condition on the basis of the measured blood flowvolumes of the person's forehead and the portions under the person'seyes Since the blood flow volume of the portions under a person's eyesbecomes high relative to the blood flow volume of the person's foreheadwhen the person is intoxicated and the blood flow volume of the portionsunder the person's eyes becomes low relative to the blood flow volume ofthe person's forehead when the person is sick due to intoxication, thelevel of intoxication of the person can be estimated.

If the physical condition estimation apparatus 10 in the present exampleis installed in a vehicle and estimates that the level of intoxicationof the person is equal to or higher than a certain value, that is, ifthe person is intoxicated, the physical condition estimation apparatus10 may control an engine of the vehicle such that the engine does notstart (device control). As a result, an intoxicated person is preventedfrom driving the vehicle.

If the physical condition estimation apparatus 10 in the present exampleestimates that the level of the intoxication of the person is equal toor higher than the certain value, that is, if the person has drunk toomuch, the physical condition estimation apparatus 10 may notify theperson of the result of the estimation or display the level ofintoxication of the person to the person. As a resist, the person canunderstand the level of intoxication thereof and it becomes possible toprevent the person from drinking too much again.

The method for estimating the level of intoxication of a person as theperson's physical condition is not limited to the one based on the bloodflow volumes of at least two body parts. The level of intoxication ofperson may be estimated on the basis of the person's facial expression,heartrate, blood pressure, blood flow, or exhaled air, instead. Since,when a person gets intoxicated, the person's line of sight becomesunstable, the person's circulation of the blood improves and theperson's heartrate increases, the person's face turns red, the personbecomes relaxed and the person's blood pressure decreases, and thealcohol concentration of the person's exhaled air increases, the levelof intoxication of the person can be estimated. One, some, or all ofthese pieces at information may be used to estimate the lever ofintoxication of a person.

Sixth Example

In the sixth example, a case will be described in which a person'sdriving skills are estimated as the person's physical condition.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the person's driving skills as the person's physicalcondition on the basis of the measured blood flow is of the person'sforehead and the portions under the person's eyes. Since a person doesnot become tense and the blood flow volume of the portions under theperson's eyes becomes high relative to the blood flow volume of theperson's forehead when the person's driving skills are high and a personbecomes tense and the blood flow volume of the portions under theperson's eyes becomes low relative to the blood flow volume of theperson's forehead when the person's driving skins are low, the person'sdriving skins can be estimated.

If the physical condition estimation apparatus 10 in the present exampleestimates that the person's driving skills are lower than a certainvalue, that is, if the person is tense during driving, the physicalcondition estimation apparatus 10 may increase the sensitivity of brakesto keep a distance to a vehicle ahead or may decrease the sensitivity ofan accelerator to keep the speed of the vehicle low. As a result, theperson becomes relaxed during driving even if the person's driving skinsare low and the person has been tense.

The method for estimating a person's driving skins as the person'sphysical condition is not limited to the one based on the blood flowvolumes of at least two body parts. A person's driving skills may beestimated from the person's facial expression or variation in theperson's heartrate. Since whether a person is relaxed can be estimatedfrom the person's facial expression and variation in the person'sheartrate becomes small when the person is tense during driving andlarge when the person is relaxed, the person's driving skills can beestimated. One, some, or all of these pieces of information may be usedto estimate a person's driving skills.

If the physical condition estimation apparatus 10 in the present exampleis installed in a vehicle and estimates a person's physical condition onthe basis of the person's facial expression, the physical conditionestimation apparatus 10 may estimate a person's fear as the person'sphysical condition. For example, the physical condition estimationapparatus 10 in the present example estimates, on the basis of aperson's facial expression, whether the person, who is inside thevehicle, is afraid during automated driving. If the physical conditionestimation apparatus 10 estimates that the person is afraid, that is, ifthe person is tense (does not trust the automated driving), the physicalcondition estimation apparatus 10 may control a vehicle device such thata distance to a vehicle ahead increases and the speed of the vehicledecreases. As a result, the person in the vehicle feels safe.

If the physical condition estimation apparatus 10 in the present exampledetects, on the basis of a person's facial expression, that the personis looking out over scenery, the physical condition estimation apparatus10 may control a vehicle device such that the speed of the vehicledecreases. As a result, the person can enjoy the scenery.

Seventh Example

In the seventh example, a case will be described in which a person'shunger level is estimated as the person's physical condition.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the person's hunger level as the person's physicalcondition on the basis of the measured blood flow volumes of theperson's forehead and the portions under the person's eyes. Since theblood flow volume of the portions under a person's eyes becomes lowrelative to the blood flow volume of the person's forehead when theperson's hunger level is high and the person is stressed, the person'shunger level can be estimated.

If the physical condition estimation apparatus 10 in the present exampleis installed in an office and estimates that a person's hunger level isequal to or higher than a certain value, that is, that the person ishungry, the physical condition estimation apparatus 10 may controllighting such that a blue component included in the light increases(device control). This is because a person becomes less hungry whenseeing blue light.

If the physical condition estimation apparatus 10 in the present exampleis installed in a vehicle and estimates that a person's hunger level isequal to or higher than the certain value, that is, that the person ishungry, the physical condition estimation apparatus 10 in the presentexample may display a nearby restaurant on a screen of a car navigationsystem and guide the person to the restaurant.

The method for estimating a person's hunger level as the person'sphysical condition is not limited to the one based on the blood flowvolumes of at least two body parts. A person's hunger level may beestimated from the person's blood sugar level or exhaled air or soundfrom the person's abdomen, instead. Since, when the person is hungry, aperson's blood sugar level decreases, the amount of acetone included inthe person's exhaled air increases, and the person's gastrointestinalactivity increases, the person's hunger level can be estimated. One,some, or all of these pieces of information may be used to estimate aperson's hunger level.

Eighth Example

In the eighth example, a case will be described in which a person'sfatigue level is estimated as the person's physical condition.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the person's fatigue level as the person's physicalcondition on the basis of the measured blood flow volumes of theperson's forehead and the portions under the person's eyes. Since theblood flow volume of the portions under the person's eyes becomes lowrelative to the blood flow volume of the person's forehead when theperson is fatigued and stressed, the person's fatigue level can beestimated.

If the physical condition estimation apparatus 10 in the present exampleis installed in a vehicle and estimates that a person's fatigue level isequal to or higher than a certain value, the physical conditionestimation apparatus 10 may control a vehicle device in such a way as tourge the person to take a break or switch to automated driving in orderto suppress the fatigue of the person, who is a driver.

The method for estimating a person's fatigue level as the person'sphysical condition is not limited to the one based on the blood flowvolumes of at least two body parts. A person's fatigue level may beestimated from the person's facial expression or oxygen saturation orlactic acid concentration in blood flow, instead. Since, when a personis fatigued, the oxygen saturation in blood flow decreases, the lacticacid concentration in the blood flow increases and the person's facelooks fatigued, the person's fatigue level can be estimated. One, some,or all of these pieces of information may be used to estimate a person'sfatigue level.

Ninth Example

In the ninth example, a case will be described in which a person'sdepression level is estimated as the person's physical condition.

In the present example, for example, the physical condition estimationapparatus 10 measures the blood flow volumes of the person's foreheadand the portions under the person's eyes as the blood flow volumes ofthe at least two body parts. The physical condition estimation apparatus10 then estimates the person's depression level as the person's physicalcondition on the basis of the measured blood flow volumes of theperson's forehead and the portions under the person's eyes. Since theblood flow volume of the portions under a person's eyes becomes lowrelative to the blood flow volume of the person's forehead when theperson is depressed and stressed, the person's depression level can beestimated.

If the physical condition estimation apparatus 10 in the present exampleestimates that a person's depression level is equal to or higher than acertain value, that is, that the person is depressed, the physicalcondition estimation apparatus 10 may control lighting in a room. Bycontrolling the lighting in the room such that, for example, thelighting becomes bright in the morning and dim at night, the person'scircadian rhythm can be adjusted and the person becomes less depressed.If the physical condition estimation apparatus 10 in the present exampleestimates that a person's depression level is equal to or higher thanthe certain value, that is, that the person is depressed, the physicalcondition estimation apparatus 10 may control an audio system such thatthe audio system plays back encouraging songs in the morning andrelaxing songs at night.

The method for estimating a person's depression level as the person'sphysical condition is not limited to the one based on the blood flowvolumes of at least two body parts. A person's depression level may beestimated from the person's facial expression or heartrate, instead.Since a period of time for which a person's parasympathetic nervoussystem remains active in a day decreases when the person is depressed,and since the period of time for which the person's parasympatheticnervous system remains active can be identified by checking temporalvariation in the person's heartrate, the person's depression level canbe estimated. In addition, it is known that when a person is depressed,facial expressions unique to a depressed person (e.g., a vacuousexpression) are observed. Whether a person is depressed, therefore, canbe estimated from the person's facial expression at a certain timingsuch as rising or a change in the person's facial expression at a timewhen a certain image is displayed. One, some, or all of these pieces ofinformation may be used to estimate a person's depression level.

Second Embodiment

Although a person's physical condition is estimated on the basis ofphysiological values such as the blood flow volumes of at least two bodyparts of the person in the first embodiment, the method for estimating aperson's physical condition is not limited to this. A person's physicalcondition may be estimated on the basis of the person's physiologicalvalues and then corrected on the basis of the person's emotion at a timewhen the physiological values are obtained. This case will be describedhereinafter as a second embodiment.

Configuration of Physical Condition Estimation Apparatus

FIG. 12 is a block diagram illustrating the configuration of a physicalcondition estimation apparatus 20 according to the second embodiment.The same components as those illustrated in FIG. 1 and other drawingsare given the same reference numerals, and detailed description thereofis omitted.

As illustrated in FIG. 12 , the physical condition estimation apparatus20 includes the blood flow measuring unit 11, a physical conditionestimation unit 22, the output control unit 13, and an emotionestimation unit 24. The physical condition estimation apparatus 20 isimplemented as a computer or the like. The physical condition estimationapparatus 20 illustrated in FIG. 12 is different from the physicalcondition estimation apparatus 10 according to the first embodiment inthat the physical condition estimation apparatus 20 includes the emotionestimation unit 24 and the configuration of the physical estimation unit22 is different from that of the physical condition estimation unit 12.

Emotion Estimation Unit 24

The emotion estimation unit 24 estimates a person's emotion on the basisof the person's physiological value. More specifically, the emotionestimation unit 24 estimates a person's emotion using Russell'scircumplex model illustrated in FIG. 4 on the basis of the person'sphysiological value. The physiological value is data regarding afunction of a living body and may indicate at least, for example,complexion, a heartrate, variation in the heartrate, a ratio of alow-frequency (LF) component to a high frequency (HF component (LF/HF)of the variation in the heartrate, R-R intervals, a pulse wave,variation in the pulse wave, a brain wave, a respiratory rate,respiratory volume, blood flow, variation in the blood flow, bloodpressure, variation in the blood pressure, oxygen saturation (SpO₂), themovement of a body part, the movement of a body muscle, the movement ofa facial muscle, body temperature, skin temperature, skin conductance,skin resistance, the coarseness of the skin, the shininess of the skin,the amount of sweat, or a sweating rate. The movement of a body part maybe, for example, blinking frequency, a blinking rate, or the like.

That is, the emotion estimation unit 24 may estimate a person's emotion,such as an arousal level of the person, on the basis of one of the bloodflow volumes of the at least two body parts measured by the blood flowmeasuring unit 11 as the person's physiological value. Alternatively,the emotion estimation unit 24 may estimate a person's emotion, such asthe arousal level of the person, on the basis of a blood flow volume ofa body part different from the blood flow volumes of the at least twobody parts measured by the blood flow measuring unit 11 as the person'sphysiological value. Alternatively, the emotion estimation unit 24 mayestimate, as a person's physiological value, the person's emotion on thebasis of, for example, a physiological value such as facial expression,the heartrate, respiration, the pulse wave, the blood pressure, or anycombination thereof.

Alternatively, the emotion estimation unit 24 may estimate a person'semotion by determining a position along a pleasure axis on the basis ofthe person's facial expression and a position along an arousal axis onthe basis of person's physiological value such as the blood flow,heartbeats, the respiration, the pulse wave, or the blood pressure usingRussell's circumplex model illustrated in FIG. 4 . This case will bedescribed hereinafter.

FIG. 13 is a block diagram illustrating an example of a detailedconfiguration of the emotion estimation unit 24 illustrated in FIG. 12 .FIG. 14A is a diagram illustrating an example of a mode in which theemotion estimation unit 24 illustrated in FIG. 12 uses Russell'scircumplex model. FIG. 14B is a diagram illustrating an example ofSchlosberg's conic model used by the emotion estimation unit 24illustrated in FIG. 12 .

As illustrated in FIG. 13 , the emotion estimation unit 24 includes acamera section 241, a facial expression estimation section 242, anemotion estimation processing section 243, and a storage section 244.

A person experiences various emotions such as pleasure and astonishment.In Russell's circumplex model illustrated in FIG. 4 , various emotionsexperienced by a person are mapped on a plane defined by a pleasure axisand an arousal axis. Russell's circumplex model illustrated in FIG. 4indicates that various emotions experienced by a person can be mapped ina circle. It might be difficult to determine a position along thearousal axis on the basis of a person's facial expression, but theposition can be calculated from the person's physiological valuedescribed above, such as the person's heartrate. A position along thepleasure axis, on the other hand, may be calculated from a person'sfacial expression. In doing so, the person's emotion can be estimatedmore accurately than when the person's emotion is estimated only on thebasis of the person's facial expression and physiological value.

The storage section 244 stores, for example, data corresponding toRussel s circumplex model illustrated in FIG. 14 .

The camera section 241 captures an image of the entirety of a person'sface. The facial expression estimation section 242 estimates theperson's facial expression on the basis of the image of the person'sface captured by the camera section 241.

The emotion estimation processing section 243 refers, for example, tothe data corresponding to Russel's circumplex model illustrated in FIG.14 stored in the storage section 244. The emotion estimation processingsection 243 may determine a person's emotion by determining a positionalong the pleasure axis on the basis of the person's facial expressionestimated by the facial expression estimation section 242 and a positionalong the arousal axis on the basis of the blood flow volumes of the atleast two body parts measured by the blood flow measuring unit 11.Alternatively, as described above, the emotion estimation processingsection 243 may determine a position along the arousal axis on the basisof physiological data such as the heartbeats, the respiration, the pulsewave, or the blood pressure. For example, the emotion estimationprocessing section 243 may determine a position along the arousal axisby estimating the person's heartrate from slight changes in the person'scomplexion estimated by the facial expression estimation section 242. Anemotion may be calculated not only when an estimated physical conditionis corrected but also when only the emotion is obtained.

Although a case in which an emotion is estimated using Russell'scircumplex model has been described, another model may be used, instead.In Schlosberg's conic model illustrated in FIG. 14B, for example, atension level, which indicates whether a person is tense or sleepy, maybe calculated from a physiological value, and whether or not the personis pleasant and whether or not the person is paying attention, which areindicated in a circle, may be calculated from the person's facialexpression. Alternatively, whether or not the person is paying attentionmay also be calculated from a physiological value. In doing so, anemotion can be estimated more accurately.

Physical Condition Estimation Unit 22

FIG. 15 is a block diagram illustrating an example of a detailedconfiguration of the physical condition estimation unit 22 illustratedin FIG. 12 . The same components as those illustrated in FIG. 3 aregiven the same reference numerals, and detailed description thereof isomitted.

As illustrated in FIG. 15 , the physical condition estimation unit 22includes the blood flow volume obtaining section 121, the physicalcondition estimation processing section 122, an estimated emotionobtaining section 223, and a correction section 224. The physicalcondition estimation unit 22 estimates a person's physical condition onthe basis of the blood flow volumes of the at least two body partsmeasured by the blood flow measuring unit 11. The physical conditionestimation unit 22 illustrated in FIG. 15 is different from the physicalcondition estimation unit 12 according to the first embodimentillustrated in FIG. 3 in that the physical condition estimation unit 22includes the estimated emotion obtaining section 223 and the estimatedemotion obtaining section 223.

More specifically, the estimated emotion obtaining section 223 obtains aperson's emotion estimated by the emotion estimation unit 24. Thecorrection section 224 corrects the person's physical conditionestimated by the physical condition estimation processing section 122 onthe basis of the person's emotion estimated by the emotion estimationunit 24.

A case will be described in which, for example, the blood flow volumemeasurement processing section 112 has estimated a certain level ofstiffness in the shoulders as a person's physical condition and theemotion estimation unit 24 has estimated “excited” as the person'semotion. Because “excited” contributes to increasing the blood flowvolume of the person and reducing the stiffness in the shoulders, thecorrection section 224 corrects the person's physical condition to alevel of stiffness in the shoulders lower than the certain level. Thephysical condition estimation unit 22 can thus obtain a result ofestimation by correcting a person's physical condition on the basis ofthe person's emotion.

Operation of Physical Condition Estimation Apparatus 20

Next, the operation of the physical condition estimation apparatus 20will be described with reference to FIG. 16 . FIG. 16 is a flowchartillustrating an overview of the operation of the physical conditionestimation apparatus 20 illustrated in FIG. 12 . The operation of thephysical condition estimation apparatus 20 is achieved by the computerincluded in the physical condition estimation apparatus 20.

First, the physical condition estimation apparatus 20 simultaneouslymeasures the blood flow volumes of at least two body parts of a person(S21). Next, the physical condition estimation apparatus 20 estimatesthe person's physical condition on the basis of the measured blood flowvolumes of the at least two body parts (S22). Next, the physicalcondition estimation apparatus 20 estimates the person's emotion on thebasis of a blood flow volume of at least one body part (S23). The bloodflow volume of the at least one body part for estimating the person'semotion may be the blood flow volume of at least one of the at least twobody parts measured to estimate the person's physical condition or maybe another body part. Next, the physical condition estimation apparatus20 corrects the person's physical condition estimated in 322 on thebasis of the person's emotion estimated in S23 (S24). The physicalcondition estimation apparatus 20 then performs output control accordingto the resultant physical condition (S25).

Advantageous Effects, Etc.

As described above, with the method for estimating a physical conditionaccording to the present embodiment and the like, a person's physicalcondition can be estimated without preliminary calibration even when acomputer estimates the person's physical condition by measuring a bloodflow volume that varies between individuals. Furthermore, with themethod for estimating a physical condition according to the presentembodiment and the like, the estimated physical condition can becorrected on the basis of the person's emotion. The person's physicalcondition that takes into consideration the person's emotion, therefore,can be estimated.

A case will be described hereinafter, as an example, in which a physicalcondition to be estimated is a level of stiffness in the shoulders andan emotion to be estimated is a level of excitement.

EXAMPLE

FIG. 17 is a diagram illustrating an example of output control performedby a physical condition estimation apparatus 20A in an example of thesecond embodiment.

In the present example, for example, a blood flow measuring unit 11Ameasures a blood flow volume A of a forehead of the person 50, a bloodflow volume B of a neck B of the person 50, and a blood flow volume C ofa nose C of the person 50 as the blood flow volumes of the at least twobody parts. An emotion estimation unit 24A estimates the level ofexcitement of the person 50 as the emotion of the person 60 on the basisof the measured blood flow volume C of the nose C.

First, the physical condition estimation unit 22 estimates the level ofstiffness in the shoulders of the person 50 as the physical condition ofthe person 50 on the basis of the blood Plow volume A of the forehead Aand the blood flow volume B of the neck B. The physical conditionestimation unit 22 then corrects the estimated level of stiffness in theshoulders of the person 50 on the basis of the level of excitement ofthe person 50 estimated by the emotion estimation unit 24A.

An output control unit 13A then displays, as the output controlaccording to the estimated physical condition of the person 50, thecorrected level of stiffness in the shoulders on a screen 62 of themobile terminal 60 owned by the person such as a smartphone.

Although an estimated physical condition of a person is corrected n thebasis of the person's emotion in the present embodiment and example, theoperation performed is not limited to this. An estimated emotion of aperson may be corrected on the basis of an estimated physical conditionof the person, instead. This case will be described hereinafter as firstand second modifications.

First Modification

A case will be described hereinafter, as the first modification, inwhich a physical condition to be estimated is hours of sleep of the dayand an emotion to be estimated is a level of sleepiness.

FIG. 18 is a diagram illustrating an example of output control performedby a physical condition estimation apparatus 20B according to the firstmodification of the second embodiment.

In the present modification, for example, a blood flow measuring unit11B measures the blood flow volume A of the forehead A of the person 50,the blood flow volume B of portions B under the eyes of the person 50,and the blood flow volume C of a nose C of the person 50 as the bloodflow volumes of the at least two body parts. First, the physicalcondition estimation unit 22 estimates the hours of sleep of the day ofthe person 50 as the physical condition of the person 50 on the basis ofthe blood flow volume A of the forehead A and the blood flow volume B ofthe portions B under the eyes.

An emotion estimation unit 24B estimates the level of sleepiness of theperson 50 as the emotion of the person 50 on the basis of the hours ofsleep of the day of the person 50 estimated by the physical conditionestimation unit 22 and the blood flow volume C of the nose C measured bythe blood flow measuring unit 11B. More specifically, first, since theskin temperature of a person' nose increases when the person is sleepy,the emotion estimation unit 24B can estimates the level of sleepiness(arousal level) on the basis of the blood flow volume C measured by theblood flow measuring unit 11B. Next, the emotion estimation unit 24B maycorrect the level of sleepiness estimated on the basis of the blood flowvolume C to a higher level of sleepiness if the hours of sleep of theday of the person 50 estimated by the physical condition estimation unit22 is short (e.g., shorter than average hours of sleep of the person50).

An output control unit 13B may, as output control, display the resultantlevel of sleepiness on a screen 63 of the mobile terminal 60, such as asmartphone, of the person 50.

The physical condition estimation apparatus 20B may thus correctestimated emotion on the basis of an estimated physical condition.

The physical condition to be estimated may be the sense of warmth andcoldness instead of the hours of sleep of the day, if estimating, as thephysical condition of the person 50, that the person 50 is feeling cold,for example, the physical condition estimation apparatus 20B may reducethe level of sleepiness estimated as the emotion of the person 50. Thephysical condition to be estimated may be whether the shoulders of theperson 50 are stiff and the emotion to be estimated may be the comfortof the person 50. If estimating, as the physical condition of the person50, that the shoulders of the person 50 are stiff, for example, thephysical condition estimation apparatus 20B may reduce the comfort ofthe person 50 estimated as the emotion of the person 50.

Second Modification

Although a case in which the emotion of the person 60 is estimated fromthe blood flow volume of the nose of the person 50 has been described inthe first modification, the emotion of the person 50 need not beestimated on the basis of the blood flow volume of the nose of theperson 50. As described above, the emotion of the person 50 may beestimated on the basis of an image of the face of the person 50 capturedby the camera section 241, instead. This case will be describedhereinafter as the second modification. In the present modification, thephysical condition to be estimated is the sense of warmth and coldness,and the emotion to be estimated is the level of sleepiness.

FIG. 19 is a diagram illustrating an example of output control performedby a physical condition estimation apparatus 20C according to the secondmodification of the second embodiment.

In the present modification, for example, the blood flow measuring unit11 measures the blood flow volume A of the forehead A of the person 50and the blood flow volume B of the portions B under the eyes of theperson 50 as the blood flow volumes of the at least two body parts.First, the physical condition estimation unit 22 estimates the sense ofwarmth and coldness of the person 50 as the physical condition of theperson 50 on the basis of the blood flow volume A of the forehead A andthe blood flow volume B of the portions B under the eyes.

The emotion estimation unit 24 estimates the level of sleepiness of theperson 50 as the emotion of the person 50 on the basis of the sense ofwarmth and coldness of the person 50 estimated by the physical conditionestimation unit 22 and an image of the entirety of the face of theperson 50 captured by the emotion estimation unit 24.

More specifically, first, the emotion estimation unit 24 captures animage of the entirety of the face of the person 50. The emotionestimation unit 24 then estimates a heartrate of the person 50 fromslight variation in the complexion of the person 50 and determines aposition along the arousal axis illustrated in FIG. 14 . The emotionestimation unit 24 also determines a position along the pleasure axisfrom a facial expression estimated from the image of the entirety of theface of the person 50. As a result, the emotion estimation unit 24 canestimates the level of sleepiness of the person 50 as the emotion of theperson 50 from the captured image of the entirety of the face of theperson 50. The emotion estimation unit 24 then corrects the level ofsleepiness estimated from the image of the entirety of the face of theperson 50 on the basis of the sense of warmth and coldness of the person50 estimated by the physical condition estimation unit 22. If thephysical condition estimation unit 22 estimates, as the physicalcondition of the person 50, that the person 50 is feeling cold, forexample, the emotion estimation unit 24 may reduce the level ofsleepiness of the person 50 estimated as the emotion of the person 50.

An output control unit 13C may display, as output control, the resultantlevel of sleepiness on a screen 63C of the mobile terminal 60, such as asmart hone, of the person 50.

The physical condition estimation apparatus 20C may thus correct anestimated emotion on the basis of an estimated physical condition.

Although the processes in the present disclosure has been described withreference to the first and second embodiments, a person or an apparatusthat dorms each process is not particularly limited.

As described above, the physical condition estimation apparatus mayinclude the blood flow measuring unit, the physical condition estimationunit, and the output control unit, for example, but may include only thephysical condition estimation unit or only the physical conditionestimation unit and the output control unit. Alternatively, The physicalcondition estimation unit and the output control unit may be achieved bya cloud server provided in a place different from a place where thelocal apparatus is provided, in this case, the cloud server and thelocal apparatus may share processing or control. For example, the cloudserver may perform heavy processing or control, and the local apparatusmay perform light processing or control. The cloud server and the localapparatus may together be referred to as a “physical conditionestimation apparatus”.

The physical condition estimation apparatus may be implemented as aprocessor or the like incorporated into a particular locally providedapparatus (described hereinafter).

-   -   (1) More specifically, the physical condition estimation        apparatus is a computer system including a microprocessor, a        read-only memory (ROM), a random-access memory (RAM), a hard        disk unit, a display unit, a keyboard, and a mouse. The RAM or        the hard disk unit stores a computer program. When the        microprocessor operates in accordance with the computer program,        the physical condition estimation apparatus achieves functions        thereof. The computer program includes a plurality of command        codes for issuing instructions to the computer system in order        to achieve certain functions.    -   (2) Part or all of the components of the physical condition        estimation apparatus may be implemented as a single large-scale        integration (LSI) circuit. A system LSI circuit is a        super-multifunctional LSI circuit fabricated by integrating a        plurality of components on a single chip. More specifically, the        system LSI circuit is a computer system including a        microprocessor, a ROM, and a RAM. The RAM stores a computer        program. When the microprocessor operates in accordance with the        computer program, the system LSI circuit achieves functions        thereof.    -   (3) Part or all of the components of the physical condition        estimation apparatus may be implemented as an integrated circuit        (IC) or a separate module removably attached to the physical        condition estimation apparatus. The IC card or the module is a        computer system including a microprocessor, a ROM, and a RAM.        The IC card or the module may also include the        super-multifunctional LSI circuit. When the microprocessor        operates in accordance with, a computer program, the IC card or        the module achieves functions thereof. The IC card or the module        may be tamper-resistant.    -   (4) The present disclosure may be the above-described method.        The present disclosure may be a computer program that implements        the method using a computer or may be a digital signal including        the computer program.    -   (5) The present disclosure may be a computer-readable recording        medium storing the computer program or the digital signal, such        as a flexible disk, a hard disk, a CD-ROM, a magneto-optical        (MO) disk, a digital versatile disc (DVD), a DVD-ROM, a DVD-RAM,        a Blu-ray disc (BD, registered trademark), or a semiconductor        memory. The present disclosure may be the digital signal stored        in one of these computer-readable recording media.

The present disclosure may be the computer program or the digital signaltransmitted through an electrical communication line, a wireless orwired communication line, a network typified by the Internet,datacasting, or the like.

The present disclosure may be a computer system including amicroprocessor and a memory. The memory may store the computer program,and the microprocessor may operate in accordance with the computerprogram.

The present disclosure may be implemented as an independent computersystem by recording the computer program or the digital signal on one ofthe computer-readable recording media and transporting thecomputer-readable recording medium or by transporting the computerprogram or the digital signal through the network or the like.

-   -   (6) The above embodiments and modifications may be combined with        one another.    -   (7) A person's physical condition may be different from those        described in the first and second embodiments. A person's        physical condition may be an epileptic seizure, Meniere's        syndrome, dizziness, or the like. In this case, a physiological        value such as the blood flow volume of a person may or may not        be used in order to estimate the person's physical condition. A        method for estimating a person's physical condition other than        those described in the first and second embodiments and the like        will be described hereinafter.

Epileptic Seizure

A method for estimating an epileptic seizure as a person's physicalcondition and an output at a time when an epileptic seizure has beenestimated will be described.

The occurrence of an epileptic seizure can be estimated (detected) froma person's line of sight or respiration or the diameter of the person'spupils. This is because it is known that a person's line of sight isfixed, the person's respiration becomes irregular, and light reflex fromthe person's pupils disappears due to an epileptic seizure. An epilepticseizure, therefore, can be estimated (detected) as a person's physicalcondition by measuring the persons light of sight or respiration or thediameter of the person's pupils.

FIG. 20 is a flowchart illustrating an example of the estimation of anepileptic seizure and an output control method.

As illustrated in FIG. 20 , first, for example, a person's line of sightis detected (S31), and whether an epileptic seizure has occurred to theperson is estimated on the basis of the person's line of sight (S32).Whether an epileptic seizure has occurred to the person may be estimatedusing one, some, or all of the person's line of sight and respirationand the diameter of the person's pupils.

Next, if it is estimated that an epileptic seizure has not occurred tothe person (NO in S32), the process returns to S31. On the other hand,if it is estimated that an epileptic seizure has occurred to the person(YES in S32) and the person is inside a vehicle, a device control signalfor controlling a device such as brakes, an accelerator, or an activesuspension of the vehicle is output (S33).

Furthermore, if the person is inside an automobile in an automateddriving mode, the automobile automatically parks in a safe place or goesto a closest hospital (S34). In S34, the automobile may call a closestambulance or security center.

Meniere's Syndrome and Dizziness

Next, a method for estimating Meniere's syndrome or dizziness as aperson's physical condition and an output at a time when Meniere'ssyndrome or dizziness has been estimated will be described.

By detecting a person's line of sight, whether Meniere's syndrome ordizziness has occurred to the person can be estimated (detected). Thisis because it is known that a person's line of sight runs in circleswhen dizziness or Meniere's syndrome has occurred to the person.

If it is estimated (detected) that Meniere's syndrome or dizziness hasoccurred to a person end the person is inside an automobile in anautomated driving mode, a device such as brakes, an accelerator, or anactive suspension of the vehicle may be controlled in such a way as toautomatically park the automobile in a safe place. Needless to say, theautomobile may immediately call a closest ambulance or security centeror may go to a closest hospital through automated driving.

Various Diseases

Alternatively, one of the following diseases may be estimated (detected)as a person's physical condition from a constituent or a secretion ofexhaled air.

If the amount of ammonia included in a person's exhaled air is large,for example, a decrease in a kidney or liver function of the person,deterioration of an intestinal environment, or gout can be detected. Ifthe amount of nitric oxide included in a person's exhaled air is large,for example, bronchial asthma or sleepiness of the person can bedetected. If the amount of hydrogen sulfide included in a person'sexhaled air is large, for example, a gastrointestinal disorder of theperson can be detected. If the amount of 3-methyl-3-sulfanyl-hexan-1-olincluded in a person's exhaled air is large, for example, it can beestimated that the person is psychologically stressed.

For example, a sensor capable of detecting one of the above-mentionedchemical substances may be provided on a desk or a mouse in a personsoffice, and if one of the above-mentioned disorders is detected as theperson's physical condition, the person or a medical department may benotified of the detection. As a result, the person can be protected fromvarious diseases.

Deep Body Temperature

The deep body temperature of e person may be estimated as the person'sphysical condition.

By detecting the body surface temperature of a person, the deep bodytemperature of the person can be estimated. The temperature of theforehead, for example, is known to be close to the deep bodytemperature. By detecting the temperature of the forehead or the likeusing a thermal camera, the deep body temperature can be estimated. Ifambient temperature is also measured and the body surface temperature iscorrected, the deep body temperature can be estimated more accurately.The deep body temperature may be estimated more accurately by alsomeasuring the temperature of a body part such as an eyeball.

An example of output control when the deep body temperature is estimated(detected) will be described hereinafter.

FIG. 21 is a diagram illustrating an example of output control dependingon a result of detection of deep body temperature. FIG. 22 is aflowchart illustrating an example of an output control method dependingon the result of the detection of the deep body temperature.

As illustrated in FIG. 21 , the deep body temperature of a patient 51 infront of a hospital can be measured in a noncontact manner by detectingthe temperature of the forehead of the patient 51 using a thermal camera40. Since a heat generation state of the patient 51 can be detected bydetecting the deep body temperature of: the patient 51 before thepatient 51 enters a hospital, for example, one of entrances to thehospital (waiting rooms) may automatically open in accordance with theheat generation state.

That is as illustrated in FIG. 22 , first, the deep body temperature ofthe patient 51 is detected using the thermal camera 40 (S41), and it isdetermined whether the deep body temperature of the patient 51 is equalto or higher than 38° C., higher than 37° C. but lower than 38° C., orequal to or lower than 37° C. (S42).

In S42, if the deep body temperature of the patient 51 is equal to orhigher than 38° C., for example, a door A of a waiting room Aautomatically opens (S43). If the deep body temperature of the patient51 is higher than 37° C. but lower than 38° C., a door B of a waitingroom B automatically opens (S44). If the deep body temperature of thepatient 51 is equal to or lower than 37° C., a door C of a waiting roomC automatically opens (S45).

As a result, a patient 51 having a high fever enters a room differentfrom one in which a patient 51 whose temperature is normal is waiting,and the patient 51 whose temperature is normal does not get infectedfrom the patient 51 having a high fever.

The thresholds of deep body temperature may be different, from thoseillustrated in FIGS. 21 and 22 , and may be adjusted in accordance withage. This is because it is known that temperatures of younger people arerelatively high. A patient's age may be registered to the patient'smedical card, and the patient may hold the medical card out toward areader. The reader and the thermal camera 40 together achieve theestimation of the deep body temperature of the patient.

A taxi may implement this estimation method. In this case, a driver ofthe taxi can, as necessary, decline to pick up a patient having a highfever, and a secondary infection to the driver can be prevented. Inaddition, in a public transportation system such as a train, differentcars may be provided for people whose temperatures are high and peoplewhose temperatures are low in this case, the prevalence of a disease canbe suppressed in the public transportation system.

The method for estimating deep body temperature and the output controlare not limited to these examples.

For example, the deep body temperature at a time of rising may bemeasured (estimated) daily. In this case, a woman's menstrual period canbe estimated. When the woman's skin tends to be dry during the estimatedmenstrual period, a humidifier or an air conditioner may beautomatically adjusted to prevent the woman's skin from becoming dry.When the woman tends to get irritated, an audio system may automaticallyselect relaxing songs.

The timing at which the deep body temperature is measured daily is notlimited to the time of rising. The deep body temperature may be measuredat any timing insofar as the measurement can be performed under the samecondition. For example, the deep body temperature may be measured at awashstand in the morning.

For example, the deep body temperature may be measured when a personarrives at his/her office. By measuring the deep body temperature whenthe person holds a card out toward a reader at an entrance of theoffice, for example, the person and the deep body temperature can beassociated with each other, and a worker having a fever can beidentified. A boss who has been informed that the worker has a fever canadjust a work schedule or urge the worker to go home, in order tomaintain the worker's health and prevent infection to other workers.

Dryness of Skin

A dryness level of a person's skin may be estimated as the person'sphysical condition.

This is because the dryness level of a person's skin can be estimated bymeasuring a water content level of the person's skin. If the drynesslevel is equal to or lower than a certain value, that is, if the watercontent level of the person's skin is equal to or lower than a certainvalue, a humidifier in a room where the person stays may be operated tohumidify the room for esthetic purposes.

Metabolic Rate

A person's metabolic rate may be estimated as the person's physicalcondition.

By measuring the temperature of a person's collarbone using a thermalcamera, a radiation thermometer, or the like, the person's metabolicrate can be estimated. It is known that when there is brown fat, themetabolic rate increases. The brown fat is located around the collarboneand generates heat. By measuring the temperature of the person'scollarbone, therefore, the person's metabolic rate can be estimated.

If a calorie intake of a person is larger than an estimated metabolicrate, for example, a warning may be issued to the person. In this case,the person can prevented from getting overweight.

Others

How a person is seated on a chair may be estimated (detected) as theperson's physical condition.

By providing a sensor for measuring the distribution of pressure in aseat of a chair, how a person is seated on the chair can be detected. Abody part likely to ache may be estimated from the detected informationand heated to prevent the pain.

Alternatively, shortness of breath of a person may be estimated(detected) as the person's physical condition.

Shortness of breath a person can be detected from a respiratory rate orthe oxygen saturation of the person. If shortness of breath is detected,the person may be notified the rhythm of respiration as a sound or thelike. As a result, the rhythm of the respiration of the person can beadjusted. By notifying the person of a rhythm of respiration slightlyslower than the actual rhythm of respiration of the person and graduallyslowing down the rhythm of respiration, the respiration of the personcan be adjusted.

Alternatively, palpitations of a person due to tension or the like maybe estimated (detected) as the person's physical condition by measuringthe person's heartrate.

If palpitations of a person due to tension or the like are detected, asound whose rhythm is slightly slower than the actual heartrate may beoutput to the person. As a result, the person's heartrate can bedecreased to relax the person. If the person is going to play a matchand needs to be tense, a sound whose rhythm is slightly faster than thatof an actual heartrate when the person is at rest may be output to theperson. As a result, an ideal tension may be achieved.

An insurance fee of life insurance or medical insurance may be adjustedin accordance with a detected type of physical condition, a degree ofthe physical condition, and a time at which the physical condition hasbeen detected. As a result, an insurance fee for a health person can bedecreased, and an insurance fee for a sick person can be increased,which is fair to all insured persons.

If a sick person is detected in a movie theater or the like, a clerk maybe notified of the detection. For example, the clerk may help the personleave the movie theater or the like. As a result, it becomes possible toprevent the person from interrupting screening.

Although the methods for estimating a person's physical condition otherthan those according to the first and second embodiments have beendescribed, the methods used are not limited to these examples. Aperson's emotion may be estimated using methods other than thataccording to the second embodiment. Such methods will be describedhereinafter while taking examples.

Level of Irritation

A level of irritation of a person, for example, may be estimated(detected) as the person's emotion.

The level of irritation can be estimated from a person's facialexpression or blood flow volume. This is because it is known that aperson's facial expression reflects irritation. This is also because itis known that when a person is irritated, a sympathetic nervous systembecomes active and peripheral blood flow decreases. Here, the level ofirritation of a person may be estimated from both the person's facialexpression and blood flow volume or either the person's facialexpression or the person's blood flow volume.

If the level of irritation of a person is estimated and the person isdriving, the sound of an engine of the person's automobile may be outputinside the automobile to make the person feel that the automobile isrunning faster than an actual speed. As a result, it becomes possible toprevent the person from driving too fast. Needless to say, if irritationof the person is estimated, the sensitivity of an accelerator of theautomobile may be reduced to prevent a sudden start or the sensitivityof brakes of the automobile may be reduced to prevent a sudden stop,instead.

Level of Sleepiness

A level of sleepiness of a person, for example, may be estimated(detected) as the person's emotion.

This is because it is known that a person's facial expression reflectssleepiness. This is also because it is known that when a person issleepy, a parasympathetic nervous system becomes active and a heartratebecomes irregular, peripheral blood flow increases and the temperatureof the peripheral skin increases, and blood pressure decreases due toexpansion of blood vessels. It is also known that when a respiratoryrate decreases, oxygen concentration decreases, and a person becomessleepy.

The level of sleepiness of a person may thus be estimated from theperson's facial expression, heartrate, respiration, blood pressure,blood flow volume, or skin temperature.

Here, the level of sleepiness of a person may be estimated from one,some, or all of the person's facial expression, heartrate, respiration,blood pressure, blood flow volume, and skin temperature.

Alternatively, a combination of these pieces of information with whichestimation accuracy becomes highest may be learned, and a differentcombination may be used for each person.

This is because some persons' facial expression clearly reflectssleepiness whereas other person's facial expression hardly reflectssleepiness. When a person's facial expression clearly reflectssleepiness, the person's facial expression may be used to estimate thelevel of sleepiness. By detecting the level of sleepiness whilecombination the person's facial expression with another physiologicalvalue, needless to say, the level of sleepiness can be accuratelyestimated. A combination used may be changed for each level ofsleepiness to be detected. In addition, some persons' blood pressuresignificantly decreases when the persons begin to become sleepy, whereasother persons' blood pressure does not. When a person fails into theformer case, blood pressure may be used to estimate the level ofsleepiness at an early timing.

These are examples, and another physiological index may be used toestimate the level of sleepiness as necessary, in this case, the levelof sleepiness can be accurately estimated. The same holds when a highlevel of sleepiness is estimated. Any physiological index may be used.As a result, an optimal physiological index can be learned and used inaccordance with the level of sleepiness to be detected, therebyachieving accurate estimation of the level of sleepiness.

If it is detected (estimated) that a person is sleepy and the person isdriving, the vehicle may be ventilated to increase oxygen concentrationinside the vehicle. In doing so, the level of sleepiness of the personcan be reduced. Alternatively, the person's sense of speed may beincreased and an arousal level of the person may be increased by openinga partition between an engine room and the drivers seat to let the soundof an engine be heard by the person. Furthermore, the arousal level ofthe person may be increased by changing the rigidness of a suspension ofthe vehicle and transmitting vibration to the person.

Method for Detecting Each Physiological Value

A method for detecting each physiological value will be describedhereinafter.

Heartrate

The heartrate can be detected by detecting slight variation in the skincolor of a face whose image has been captured by a camera. This isbecause especially a green component of the skin color of the facevaries depending on the heartrate.

Alternatively, the heartrate may be detected by detecting variation inthe temperature of a temperature range corresponding to the skin of theface whose image has been captured by a thermal camera. This is becausethe temperature of the face whose image has been captured by the thermalcamera varies depending on the heartrate and the heartrate can bedetected by detecting variation in the temperature of the temperaturerange corresponding to the skin.

Alternatively, infrared light may be radiated onto an ear robe, afinger, or the lice and the heartrate may be detected from variation inreflected infrared light. Alternatively, vibration caused by heartbeatsmay be detected using a sheet sensor or the like, and the heartrate maybe detected from a waveform of the heartbeats. Any other method may beused.

Blood Pressure

The blood pressure can be obtained from a pulse wave propagation time.The pulse wave propagation time is a time taken for blood in the heartto reach a certain peripheral part.

When blood pressure drops, the pulse wave propagation time increases,and when blood pressure rises, the pulse wave propagation timedecreases. The pulse wave propagation time can be obtained from adifference between a time of a peak of a pulse wave obtained from animage of the face captured by a camera and a time of a peak of the pulsewave obtained from an image of a body part other than the face (theneck, a hand, or the like). The pulse wave propagation time may beobtained from a difference between times of peaks of a pulse wave at twofacial parts (e.g., the jaw and the forehead), instead of the face and abody pert other than the face.

Alternatively, the vibration of the heart may be obtained from amilliwave sensor or the like, and a pulse wave in the face may bedetected from slight variation in the color of an image of the facecaptured by a camera. The pulse wave propagation time may then obtainedfrom a difference between a peak of the vibration of the heart and apeak of the pulse wave in the face, and the blood pressure may beobtained by estimating variation in the blood pressure.

Skin Moisture Level

A skin moisture level can be measured by radiating near-infrared lighthaving an absorption wavelength of water (960 nm) onto the skin anddetecting the amount of returning light. This is because when the skinmoisture level is high, the radiated near infrared light is absorbed andthe amount of returning light decreases.

A water content level (skin moisture level) may be estimated from thehardness of the skin by radiating ultrasonic waves or air and detectingvariation at the time using a milliwave sensor or the like. This isbecause it is known that the skin hardens when the skin moisture leveldecreases.

Blood Sugar Level

A blood sugar level can be obtained by radiating infrared light onto aneyeball and detecting the amount of returning light. This is because thespectrum of a part of the eyeball (aqueous humor) includes an absorptionwavelength of sugar (around 1,650 nm), and the amount of returning lightdecreases when the blood sugar level is high.

The blood sugar level may be estimated from optical rotation of the partof the eyeball (aqueous humor). This is because the optical rotationincreases as the blood sugar level becomes higher. Any other method maybe used to estimate the blood sugar level.

Constituent of Exhaled Air

A constituent of exhaled air can be detected on the basis of the amountof absorption at an absorption wavelength of the constituent to bedetected (e.g., around 225 nm in the case of nitric oxide).

A constituent of exhaled air can be detected by radiating light havingan absorption wavelength of the constituent and detecting the amount oflight that has passed through the exhaled air. A spectrum may bedetected, needless to say, using chromatography. Any other method may beused.

Respiration

Respiration can be detected by, in a camera image, radiating infraredlight having a rectangular pattern onto a subject and detecting awavelength of the respiration from variation in the pattern.

The respiration may be detected using visible light instead of infraredlight, and the pattern to be radiated need not be a rectangular pattern.A milliwave may be radiated, and the respiration may be detected from aDoppler shift in a reflected wave, instead. Alternatively, therespiration may be detected using a time-of-flight (TOF) sensor.

It is known that the temperature of the portion under the nostrilsdecreases during inhalation and increases during exhalation. A waveformof respiration, therefore, may be detected from variation in thetemperature of the portion under the nostrils using a thermal image.

The present disclosure can be applied to a method for estimating aphysical condition, a physical condition estimation apparatus, and aprogram that estimate a person's physical condition. The presentdisclosure can be applied especially to a method for estimating aphysical condition, a physical condition estimation apparatus, and arecording medium storing a program that is incorporated into devices invehicles, offices, and living spaces and device applications thatcontrol such devices.

What is claimed is:
 1. A method of controlling a device, comprising:obtaining information related to a body surface temperature of a personby detecting the body surface temperature of the person by a thermalcamera, estimating a deep body temperature of the person on the basis ofthe information related to the body surface temperature of the person,installing the thermal camera at an entrance of a hospital having afirst waiting room and a second waiting room respectively provided witha first door and a second door, in a case where the estimated deep bodytemperature of the person is in a first range, having the first door ofthe first waiting room open, and in a case where the estimated deep bodytemperature of the person is in a second range, having the second doorof the second waiting room open.
 2. The method according to claim 1,wherein the first range and the second range are adjusted according toinformation related to the person.
 3. The method according to claim 2,wherein the information related to the person is obtained by readinginformation in a medical card, when the person holds the medical cardout toward a reader in the hospital.
 4. A method of controlling adevice, comprising: obtaining information related to a body surfacetemperature of a person by detecting the body surface temperature of theperson by a thermal camera, estimating a deep body temperature of theperson on the basis of the information related to the body surfacetemperature of the person, in a case where the estimated deep bodytemperature of the person is in a first range, controlling a firstentrance of a first car of a train to open while a second entrance of asecond car of the train is closed, the train including at least thefirst car and the second car respectively provided with the firstentrance and the second entrance, in a case where the estimated deepbody temperature of the person is in a second range, controlling thesecond entrance of the second car of the train to open while the firstentrance of the first car of the train is closed.
 5. A controller of adevice, comprising: a memory that stores instructions; and a processor,when executing the instructions stored in the memory, that performsoperations including: obtaining information related to a body surfacetemperature of a person by detecting the body surface temperature of theperson by a thermal camera, estimating a deep body temperature of theperson on the basis of the information related to the body surfacetemperature of the person, installing the thermal camera at an entranceof a hospital having a first waiting room and a second waiting roomrespectively provided with a first door and a second door, in a casewhere the estimated deep body temperature of the person is in a firstrange, having the first door of the first waiting room open, and in acase where the estimated deep body temperature of the person is in asecond range, having the second door of the second waiting room open. 6.A non-transitory computer readable recording medium storing a programthat, when executed by a computer, causes the computer to performoperations comprising: obtaining information related to a body surfacetemperature of a person by detecting the body surface temperature of theperson by a thermal camera, estimating a deep body temperature of theperson on the basis of the information related to the body surfacetemperature, installing the thermal camera at an entrance of a hospitalhaving a first waiting room and a second waiting room respectivelyprovided with a first door and a second door, in a case where theestimated deep body temperature of the person is in a first range,having the first door of the first waiting room open, and in a casewhere the estimated deep body temperature of the person is in a secondrange, having the second door of the second waiting room open.